There's been some wonderful work going on at our plot in Wytham Woods.
Kim Calders (at the National Physical Laboratory and University College London) and Mat Disney (at University College London) have been scanning parts of the plot with Terrestrial Laser Scanners in summer and winter 2015. Kim has also been working on the airborne lidar data over Wytham, provided by David Coomes' team at Cambridge, and originally collected by NERC ARSF as part of the AIRSAR campaign.
Mat has written a nice post about this work here
The image show shows a transect and shows what is possible. The red dots indicate laser returns from the summer (mainly from leaves). The green dots are returns from the winter scans (manly from wood and evergreen leaves). The blue dots show what is detected from the airborne lidar in summer (mainly the top surface of the canopy).
In combination, these data depict an wonderfully detailed 3D representation of the woodland of which this is just a cross-section. This patch contains a dense patch of ash and sycamore of roughly even age and size, a legacy of recovery form disturbance in the 1940s and early 1950s. Hence the dense canopy of crowns tightly packed and competing for space, and the lack of gaps in canopy space from tree mortality. We can also begin to estimate and map leaf area and biomass by comparing winter and summer scans. Data such as these open new prospects in not just forest mapping, but in understanding forest ecology, dynamics and animal habitats. They look gorgeous too!
Below is an image of the same landscape I have taken from a drone last week (our canopy walkway is in the foreground), which when combined with the laser imagery above adds additional potential to map the distribution, shape and phenology of every tree in exquisite detail. The leaves are just beginning to come out in Wytham in the sycamore and some oak, but not yet the ash.
And finally here is a lovely video (edited together by my son Luke Malhi) showing some lovely footage of the woods and study plot from the air. We are hatching plans to do a more systematic series of drone maps to captre the seasonal shifts in the canopies of individual trees
Yadvinder Malhi is an ecosytem ecologist and Professor of Ecosystem Science at Oxford University